<template>
  <div>
    <!-- 面包屑导航区域 -->
    <el-breadcrumb separator-class="el-icon-arrow-right">
      <el-breadcrumb-item :to="{ path: '/home' }">首页</el-breadcrumb-item>
      <el-breadcrumb-item>商品管理</el-breadcrumb-item>
      <el-breadcrumb-item>添加商品</el-breadcrumb-item>
    </el-breadcrumb>
    <!-- 卡片视图 -->
    <el-card>
      <!-- 提示区域 -->
      <el-alert
        :closable="false"
        title="添加商品区域"
        type="info"
        show-icon
        center
      ></el-alert>

      <!-- 进度条区域 -->
      <el-steps
        :space="200"
        :active="activeIndex - 0"
        finish-status="success"
        align-center
      >
        <el-step title="基本信息"></el-step>
        <el-step title="商品参数"></el-step>
        <el-step title="商品属性"></el-step>
        <el-step title="商品图片"></el-step>
        <el-step title="商品内容"></el-step>
        <el-step title="完成"></el-step>
      </el-steps>

      <!-- tabs栏区域 -->
      <el-form
        :model="addForm"
        :rules="addFormRules"
        ref="addFormRef"
        label-width="100px"
        label-position="top"
      >
        <el-tabs
          :before-leave="beforeTabLeave"
          v-model="activeIndex"
          tab-position="left"
          @tab-click="tabClicked"
        >
          <el-tab-pane label="基本信息" name="0">
            <el-form-item label="商品名称" prop="goods_name">
              <el-input v-model="addForm.goods_name"></el-input>
            </el-form-item>
            <el-form-item label="商品价格" prop="goods_price">
              <el-input type="number" v-model="addForm.goods_price"></el-input>
            </el-form-item>
            <el-form-item label="商品重量" prop="goods_weight">
              <el-input type="number" v-model="addForm.goods_weight"></el-input>
            </el-form-item>
            <el-form-item label="商品数量" prop="goods_number">
              <el-input type="number" v-model="addForm.goods_number"></el-input>
            </el-form-item>
            <el-form-item label="商品分类" prop="goods_cat">
              <!-- 选择商品分类的级联选择框 -->
              <el-cascader
                v-model="addForm.goods_cat"
                :options="cateList"
                :props="cateProps"
                @change="handleChange"
              ></el-cascader>
            </el-form-item>
          </el-tab-pane>
          <el-tab-pane label="商品参数" name="1">
            <!-- 渲染参数列表 -->
            <el-form-item
              :label="item.attr_name"
              :key="item.attr_id"
              v-for="item in manyTableData"
            >
              <!-- 复选框组 -->
              <el-checkbox-group v-model="item.attr_vals">
                <el-checkbox
                  border
                  :label="value"
                  v-for="(value, index) in item.attr_vals"
                  :key="index"
                ></el-checkbox>
              </el-checkbox-group>
            </el-form-item>
          </el-tab-pane>
          <el-tab-pane label="商品属性" name="2">
            <el-form-item
              :label="item.attr_name"
              v-for="item in onlyTableData"
              :key="item.attr_id"
            >
              <el-input v-model="item.attr_vals"></el-input>
            </el-form-item>
          </el-tab-pane>
          <el-tab-pane label="商品图片" name="3">
            <!-- 图片上传,需手动指定请求头 -->
            <el-upload
              action="http://127.0.0.1:8888/api/private/v1/upload"
              :on-preview="handlePreview"
              :on-remove="handleRemove"
              list-type="picture"
              :headers="headersObj"
              :on-success="handleSuccess"
            >
              <el-button size="small" type="primary">点击上传</el-button>
              <div slot="tip" class="el-upload__tip">
                只能上传jpg/png文件，且不超过500kb
              </div>
            </el-upload>
          </el-tab-pane>
          <el-tab-pane label="商品内容" name="4">
            <quill-editor v-model="addForm.goods_introduce"></quill-editor>
            <!-- 添加商品按钮 -->
            <el-button @click="addGoods" class="addGoodsBtn" type="primary">
              添加商品
            </el-button>
          </el-tab-pane>
        </el-tabs>
      </el-form>
    </el-card>

    <!-- 图片预览 -->
    <el-dialog
      title="图片预览"
      :visible.sync="picPreviewDialogVisible"
      width="50%"
    >
      <img :src="previewPath" alt="" class="previewImg" />
    </el-dialog>
  </div>
</template>

<script>
import _ from 'lodash'

export default {
  data() {
    return {
      // 激活的步骤索引
      activeIndex: '0',
      // 添加商品的表单数据对象
      addForm: {
        goods_name: '',
        goods_price: 0,
        goods_weight: 0,
        goods_number: 0,
        // 商品所属的分类数组
        goods_cat: [],
        pics: [],
        // 商品的详情描述
        goods_introduce: '',
        // 动态参数和静态参数
        attrs: []
      },
      // 商品校验规则
      addFormRules: {
        goods_name: [
          { required: true, message: '请输入商品名称', trigger: 'blur' }
        ],
        goods_price: [
          { required: true, message: '请输入商品价格', trigger: 'blur' }
        ],
        goods_weight: [
          { required: true, message: '请输入商品重量', trigger: 'blur' }
        ],
        goods_number: [
          { required: true, message: '请输入商品数量', trigger: 'blur' }
        ],
        goods_cat: [
          { required: true, message: '请选择商品分类', trigger: 'blur' }
        ]
      },
      // 所有的商品分类数据
      cateList: [],
      // 级联选择框配置对象
      cateProps: {
        expandTrigger: 'hover',
        value: 'cat_id',
        label: 'cat_name',
        children: 'children'
      },
      // 动态参数列表数据
      manyTableData: [],
      // 静态属性列表数据
      onlyTableData: [],
      // 图片上传组件的headers请求头组件
      headersObj: {
        Authorization: window.sessionStorage.getItem('token')
      },
      // 图片预览的路径
      previewPath: '',
      // 控制图片预览对话框的显示与隐藏
      picPreviewDialogVisible: false
    }
  },
  created() {
    this.getCateList()
  },
  methods: {
    // 获取所有分类数据
    async getCateList() {
      const { data: res } = await this.$http.get('categories')
      if (res.meta.status !== 200) {
        return this.$message.error('商品分类数据获取失败!')
      }
      this.cateList = res.data
    },

    // 级联选择框选中项变化会触发此函数
    handleChange() {
      // 只允许选中三级分类
      if (this.addForm.goods_cat.length !== 3) {
        this.addForm.goods_cat = []
        return false
      }
    },

    // tab选项卡发生切换之前调用此函数
    // activeName 即将进入的标签页
    // oldActiveName 即将离开的标签页
    beforeTabLeave(activeName, oldActiveName) {
      // 阻止标签页的切换
      if (oldActiveName === '0' && this.addForm.goods_cat.length !== 3) {
        this.$message.error('请先选择商品分类!')
        return false
      }
    },

    // 监听tab标签被点击的事件
    async tabClicked() {
      // 如果点击的是商品参数标签页,则根据商品分类查询商品参数列表
      if (this.activeIndex === '1') {
        const { data: res } = await this.$http.get(
          `categories/${this.cateId}/attributes`,
          {
            params: { sel: 'many' }
          }
        )
        if (res.meta.status !== 200) {
          return this.$message.error('参数列表获取失败!')
        }
        // attr_vals的值为字符串,需转化为数组
        res.data.forEach(item => {
          item.attr_vals =
            item.attr_vals.length === 0 ? [] : item.attr_vals.split(' ')
        })
        this.manyTableData = res.data
      } else if (this.activeIndex === '2') {
        const { data: res } = await this.$http.get(
          `categories/${this.cateId}/attributes`,
          {
            params: { sel: 'only' }
          }
        )
        if (res.meta.status !== 200) {
          return this.$message.error('参数列表获取失败!')
        }
        this.onlyTableData = res.data
      }
    },

    // 处理图片预览效果
    handlePreview(file) {
      this.previewPath = file.response.data.url
      this.picPreviewDialogVisible = true
    },
    // 处理移除图片的操作
    handleRemove(file) {
      // 1.获取将要删除的图片的临时路径
      const filepath = file.response.data.tmp_path
      // 2.从pics数组中,找到这个图片对应的索引值
      const i = this.addForm.pics.findIndex(x => x.pic === filepath)
      // 3.调用数组的splice方法,把图片信息对象从pics数组中移除
      this.addForm.pics.splice(i, 1)
    },
    // 监听图片上传成功的事件
    handleSuccess(response) {
      // 封装图片对象并添加到addForm中
      const picInfo = { pic: response.data.tmp_path }
      this.addForm.pics.push(picInfo)
    },

    // 点击按钮添加商品
    addGoods() {
      // 表单预验证
      this.$refs.addFormRef.validate(async valid => {
        if (!valid) {
          return this.$message.error('请填写必要的表单项')
        }

        // 设置表单参数
        this.manyTableData.forEach(item => {
          const attrsTmp = {
            attr_id: item.attr_id,
            attr_value: item.attr_vals.join(' ')
          }
          this.addForm.attrs.push(attrsTmp)
        })
        this.onlyTableData.forEach(item => {
          const attrsTmp = {
            attr_id: item.attr_id,
            attr_value: item.attr_vals
          }
          this.addForm.attrs.push(attrsTmp)
        })

        // 将原form表单深拷贝为另一个form表单
        const form = _.cloneDeep(this.addForm)
        form.goods_cat = form.goods_cat.join(',')

        // 添加商品
        const { data: res } = await this.$http.post('goods', form)
        if (res.meta.status !== 201) {
          return this.$message.error('添加商品失败')
        }
        this.$message.success('添加商品成功')
        this.$router.push('/goods')
      })
    }
  },
  computed: {
    cateId() {
      if (this.addForm.goods_cat.length === 3) {
        return this.addForm.goods_cat[2]
      }
      return null
    }
  }
}
</script>

<style lang="less" scoped>
.el-checkbox {
  margin: 0 10px 0 0 !important;
}

.previewImg {
  width: 100%;
}

.addGoodsBtn {
  margin-top: 15px;
}
</style>
